“It’s like playing dress-up at times and other times it’s just so meaningful. And I just enjoy that so much.

“We get to walk in other people’s shoes, and life without empathy is no fun at all. And I appreciate being able to do that for my life.

“I find people endlessly fascinating, and as long as you can do that, then each project seems like something new.”

The first film to put Bale on the map was 1987’s Empire of the Sun, where he played a young English boy taken prisoner in a Japanese prisoner of war camp.

But years later, American Psycho – a dark and disturbing film which has established itself as a real cult classic – made him a huge name.

In it, Bale plays one of the most acclaimed violent and visceral characters in cinema, a performance which attracted a number of directors who subsequently cast him in a series of high-profile films such as Terminator Salvation, The Prestige, Shaft and Captain Corelli’s Mandolin.

Film critic Gary Slaymaker said winning the accolade now meant the star has a chance to further widen his repertoire.

“The world is now his oyster, he can pick and choose what kind of films he wants to do,” he said. “I like Christian Bale, I think he’s a good actor and it’s rare that a child actor goes on to become as successful.

“There’s not that many – I guess Jodie Foster is the female equivalent.

“Yet he’s one of those actors who when you are watching you feel you’re watching the actor and not the character.

“He’s a bit like Morgan Freeman or Anthony Hopkins – you feel you’re watching Christian Bale because he’s so intense.”

But, referring to his role in The Machinist, Mr Slaymaker said weight loss had little impact on how his performances are reviewed.